Pawl-and-ratchet catch

Abstract

Pawl catch device for two reciprocally-rotating parts, for example for an awning. The first part has a spring-loaded pawl with a tongue to engage with teeth on a toothed sector provided on the second part. The second part also comprises a shaft about which the first part rotates. The teeth on the toothed sector are disposed at successively increasing distances from the shaft, and the pawl is adapted to catch automatically in any of a plurality of angular positions, such that when the two parts are rotated back toward the starting position, the tongue passes clear of the top of that tooth with which it has just been engaged. The pawl is held by spring force against the teeth in each of the catch positions.

Having described my invention, I claim: 
     
       1. A pawl catch device comprising two relatively rotatable parts, the first part having a main pawl pivotally mounted thereon with a tongue that engages with the teeth on a toothed sector on the second part, said second part having a shaft about which the first part is rotatably secured, the teeth on the toothed sector being disposed at successively increasing distances from the shaft, the main pawl being adapted to catch automatically in any of a plurality of angular positions in engagement with successive ones of said teeth, said main pawl having a plurality of radially extending notches therein, an auxiliary pawl pivotally mounted on said first rotatable part, spring means urging said auxiliary pawl toward said notches, said teeth and auxiliary pawl being so positioned relative to each other that movement of said tongue from tooth to tooth along said toothed sector in the direction in which the distances of said teeth from said shaft successively increase causes said auxiliary pawl to move from notch to notch on said main pawl whereby said main pawl is held by said auxiliary pawl in such an angular position that upon reversal of the direction of rotation of the parts relative to each other, said main pawl will bypass the top of the teeth of lesser height that have been passed by said main pawl. 
     
     
       2. A device as claimed in claim 1, said auxiliary pawl having the form of a two-armed lever rotatable about a shaft on said first part, a first arm of said lever engaging with said notches and a second arm of said lever being connected by a radial tension spring to a point on said first part.